Approaches are being developed that use over the air power transmission between a transmitter and a chargeable device. One such approach is based on inductive coupling between a transmit coupler embedded, for example, in a “charging” mat or surface and a receive coupler plus rectifying circuit embedded in the chargeable device. As will be understood by a person having ordinary skill in the art, a first device, such as a wireless power receiver, may communicate with one or more other devices, such as a wireless power transmitter, by modulating a load of the receiver. This communication may be referred to as “reverse link signaling” or “in-band signaling.” In many applications, receivers are cost- and size-constrained. Further, since the receivers are often moved with respect to the transmitter, coupling as well as induced voltages in either or both of the transmitter and receiver may be highly variable. Therefore, a need exists for methods and apparatuses for reliable wireless power in-band signaling by load generation, particularly for receivers configured for different applications.